Fix all -Wnon-virtual-dtor warnings.

webrtc/p2p/p2p.gyp

 # Copyright (c) 2014 The WebRTC project authors. All Rights Reserved.
 #
 # Use of this source code is governed by a BSD-style license
 # that can be found in the LICENSE file in the root of the source
 # tree. An additional intellectual property rights grant can be found
 # in the file PATENTS.  All contributing project authors may
 # be found in the AUTHORS file in the root of the source tree.
 
 {
   'includes': [ '../build/common.gypi', ],
   'targets': [
     {
       'target_name': 'rtc_p2p',
       'type': 'static_library',
       'dependencies': [
         '<(webrtc_root)/base/base.gyp:rtc_base',
         '<(webrtc_root)/common.gyp:webrtc_common',
       ],
-      'cflags_cc!': [
-        '-Wnon-virtual-dtor',
-      ],
       'sources': [
         'base/asyncstuntcpsocket.cc',
         'base/asyncstuntcpsocket.h',
         'base/basicpacketsocketfactory.cc',
         'base/basicpacketsocketfactory.h',
         'base/candidate.h',
         'base/common.h',
         'base/dtlstransportchannel.cc',
         'base/dtlstransportchannel.h',
         'base/p2pconstants.cc',
@@ skipping 45 matching lines @@
         'base/turnserver.h',
         'base/udpport.h',
         'client/basicportallocator.cc',
         'client/basicportallocator.h',
         'client/httpportallocator.cc',
         'client/httpportallocator.h',
         'client/socketmonitor.cc',
         'client/socketmonitor.h',
       ],
       'direct_dependent_settings': {
-        'cflags_cc!': [
-          '-Wnon-virtual-dtor',
-        ],
         'defines': [
           'FEATURE_ENABLE_VOICEMAIL',
         ],
       },
       'conditions': [
         ['build_with_chromium==0', {
           'defines': [
             'FEATURE_ENABLE_VOICEMAIL',
             'FEATURE_ENABLE_PSTN',
           ],
@@ skipping 18 matching lines @@
         }],
       ],
     },
     {
       'target_name': 'libstunprober',
       'type': 'static_library',
       'dependencies': [
         '<(webrtc_root)/base/base.gyp:rtc_base',
         '<(webrtc_root)/common.gyp:webrtc_common',
       ],
-      'cflags_cc!': [
-        '-Wnon-virtual-dtor',
-      ],
       'sources': [
         'stunprober/stunprober.cc',
       ],
     },
     {
       'target_name': 'stun_prober',
       'type': 'executable',
       'dependencies': [
         'libstunprober',
         'rtc_p2p'
       ],
-      'cflags_cc!': [
-        '-Wnon-virtual-dtor',
-      ],
       'sources': [
         'stunprober/main.cc',
       ],
     },
   ],  # targets
   'conditions': [
     ['include_tests==1', {
       'targets' : [
         {
           'target_name': 'rtc_p2p_unittest',
@@ skipping 32 matching lines @@
                 ],
               }],
             ],
           },
         },  # target rtc_p2p_unittest
       ],  # targets
     }],  # include_tests==1
   ],  # conditions
 }